OneFiercePuppy: Unobtanium, handwavium, McGuffinite...that's all pretty ideal stuff for sci-fi, IMO. I mean, it's *hard* to write good, hard sci-fi that won't look silly in 20 or 50 years due to our discoveries and stuff. Going ahead and accepting that there's no known way to make your toy do what your plot requires it to do is actually pretty honest. Stargate side-eyes the physics and then tells a story; that's about the best that's fair to expect of TV, isn't it? I can't even think of any good hard sci-fi in TV or movies...like, at all. Asimov's
Foundation series has a lot of good stuff but AFAIK there's nothing extant in television or film (yet...there's always talk of making a movie or TV series). Even The Martian - which is a solid bit of hard sci-fi in novel form - takes a bunch of liberties in the film and is maybe not really
hard sci-fi in that medium.
I totally agree, I would say it's near impossible to write hard sci fi, because so many things we want to see our actually either impossible or highly improbable in real life.
Stargate does a great job because it is at least fairly consistent throughout the series in what is possible or not. And it tells good stories with interesting characters.
They've just announced they're making a prequel mini series type thing, with any luck it might lead to a new proper series further down the line.